The present invention relates to a gas-burned glue gun, and more particularly to such a gas-burned glue gun which automatically extinguishes the flame after a catalyzer has been heated to produce a heating effect, enabling the catalyzer to be burned with flameless fuel gas and heat energy to be efficiently transmitted from the catalyzer to a heat conductive glue stick tube to melt a glue stick for sealing.
A regular heat melting glue gun is generally comprised of a magnetic ignition system and a fuel gas supply system. The fuel gas supply system comprises a rechargeable fuel gas tank mounted in a hollow handle at one end of the gun body, of the heat melting glue gun, a flame nozzle connected to the fuel gas tank through a gas tube, a wheel controlled to regulate the flow rate of discharged fuel gas. The ignition system is controlled by a control button to discharge a high voltage through a wire electrode, causing sparks to be produced at the front side of the flame nozzle, and therefore discharged fuel gas is burned in a combustion chamber into which the flame nozzle is moved by means of the control of a lever. When fuel gas is burned in the combustion chamber, a glue stick is melted in a melting chamber and driven out of a glue nozzle at the front side of the glue gun. This structure of heat melting glue gun is not safe in use because it is difficult to the control the flame during the operation of the heat melting glue gun. Furthermore, it takes much time to heat the melting chamber to a higher temperature than the melting point of the glue stick installed. There is another prior art structure of heat melting glue gun which uses an electronic ignition system to ignite discharged fuel gas, and a catalyzer to improve the heating efficiency. However, the catalyzer tends to be burned out quickly when heated by a flame through a length of time. There is known still another prior art structure of heat melting glue gun which uses a rechargeable storage battery and a heating coil for heating a glue stick. However, this structure of heat melting glue gun is still not satisfactory in function, because the capacity of the rechargeable storage battery is limited, and charging the rechargeable storage battery to a saturated status takes much time. This structure of heat melting glue gun cannot completely eliminate an electric leakage. Further, the temperature of the heating coil is not adjustable when heated, and the installed glue stick tends to be over-heated.